EP0791716A1 - Safety door edge device - Google Patents

Abstract

The electric contacts comprise a first set (2) of stationary elements and a second set (3) of movable contacts alternating along the fastening between the closure edges. When not operating, the electric elements form a closed circuit. When operated, at least one movable contact of the second set is removed from at least one stationary contact of the first set and thereby breaks the circuit. The inside of the convex switch part (4) of the elastic tubing (1) has a number of T-sectioned dies (5) the ends (6) of which on their sides facing the switch part have the second set of movable contacts. The first set of stationary contacts on at least one stationary transverse bar (7) are positioned on gaps with which they overlap with the second set.

Description

The invention relates to a closing edge safety device according to the preamble of claim 1.

Closing edge safety devices of this type are used as collision protection for roller shutters, roller shutters, vehicle sliding doors and similar applications. Their purpose is to stop the motor movement, for example of a roller shutter, as soon as it hits an obstacle in order to prevent the obstacle from being damaged or a person being injured.

In order to fulfill this purpose, the closing edge safety device must run along the closing edge to be secured, that is to say it should be tubular or hose-like and trigger the desired switch-off effect as soon as it experiences external pressure at at least one point. Such a closing edge safety device is described for example in EP 0 103 726 B1. The safety strip shown there has a hose, within which a multiplicity of contacting elements are arranged, which consist of a cylindrical insulating body in which a metallic contact element is embedded, the ends of which protrude from the cylindrical insulating body by the same amount on both sides thereof. In the idle state of this safety strip, all adjacent contact elements touch each other, while in the bent state the contact elements separate from one another and the cylindrical insulating bodies touch on the edge side, as a result of which a current flowing through the contact elements is interrupted. This arrangement has the disadvantage that a relatively strong deflection is required before the contact is broken. However, the safety edge has to react to slight deflections, because otherwise it would have to be built very deep, ie impractical. A device of similar construction and with the same disadvantages is the subject of DE 29 17 797 A1 and also EP 172 136 B1.

This disadvantage is countered in EP 234 523 B1 in that, on the one hand instead of an enveloping hose, an inner rubber cord is used, on which, in addition to a first plurality of contact elements, a second plurality of insulating pieces is arranged. In the unloaded state, the contact elements come into direct contact, while when loaded, the insulating pieces slide into the gap between two contact elements and interrupt the current flowing through the contact elements.

This device has a high level of complexity due to the large number of different elements and is therefore expensive to produce and maintain.

Simpler closing edge safety devices are for example the subject of DE-U 82 27 534.3, DE 35 07 922 C2 and DT 25 16 421 A1. In the first of these publications, a collision protection for roller shutters is described, which has a compressible bellows with a U-shaped cross section with a switching device, the two legs being connected by a web arched downwards and one each at the transition between the legs and the web Notch is provided. When the overrun protection is pressed, an electrical switching element is actuated. On the one hand, this device has the disadvantage that a contact is closed when actuated (make contact principle) and not, as in the above-mentioned documents, open (make contact principle). This requires more complex evaluation electronics to control the motor. On the other hand, the rubber hose breaks slightly at the fold shown. The second-mentioned publication (DE 35 07 922 C2) describes a switch mat with two mutually opposite, mutually movable and electrically conductive contact surfaces, at least one of which is flexible. Contact between the two buttons takes place through contact windows against the pressure on electrically insulating spacers. On the one hand, this device has a flat design and is therefore unsuitable for securing the closing edge, and on the other hand it also works according to the closer principle, which has the disadvantage indicated above.

The DT 25 16 421 A1 finally describes a safety edge, in which one Hose-like sheath power lines are included, which are woven into an easily bendable textile fabric serving as a contact strip. The safety edge consists of a lower part made of rubber and an upper part, which is also made of rubber. The lower part is essentially flat, while the upper part is approximately semicircular and has on its inner side facing the lower part a projection which faces the inside of the lower part. Both the inside of the lower part and the surface of the projection are covered with an electrically conductive contact strip. As soon as pressure is exerted on the upper part, its rubber bends into a more rectangular shape and the contact strip of the projection comes into electrical contact with the contact strip of the lower part. This arrangement is of relatively simple construction and is also inexpensive to manufacture, but also has the disadvantage that it is a make contact arrangement, that is to say a more complicated evaluation electronics is required. In addition, due to the two longitudinal electrodes, the actuating force can only be set inaccurately.

There is therefore the task of developing a closing edge safety device in such a way that its actuating pressure is precisely defined and its output signal is easy to evaluate.

This object is achieved with the characterizing features of claim 1. Advantageous refinements can be found in the subclaims.

• Fig. 1 einen Querschnitt durch eine Schließkantensicherung;
• Fig. 2 einen Längsschnitt durch die Schließkantensicherung aus Figur 1; und
• Fig. 3 eine Detaildarstellung aus Figur 2 bei betätigter Schließkantensicherung.

An embodiment of the invention is described in more detail below with reference to the accompanying drawings, which show:

• 1 shows a cross section through a closing edge safety device.
• 2 shows a longitudinal section through the closing edge safety device from FIG. 1; and
• 3 shows a detailed illustration from FIG. 2 with the closing edge safety device actuated.

The closing edge safety device shown in FIGS. 1 to 3 has an elastic hose 1, preferably made of rubber or another elastomeric material, in which electrical contact elements are arranged. As shown in FIG. 1, the tube 1, seen in cross section, essentially consists of a semicircular switching area 4 on one side and an essentially rectangular fastening area 8 on the other side. The location at which the side edge of the roller door to be secured is located is identified by the reference number 9. Starting from this end 9, the rubber hose 1 initially has two protruding strips 10 with recesses 11 arranged behind it, with which it can be inserted into a corresponding receiving strip, which was previously attached to the roller door. This is followed by an essentially square area 12, formed by the fastening area 8, the two side walls 14 and two strips 7 projecting inwards from the inside of these side walls 14, which, however, do not result in a closed wall, but rather leave an intermediate space in the middle.

An approximately semicircular area 13 adjoins the square area 12, formed by the extensions of the two side walls 14, which each run in a quarter circle and merge into one another. The switching area 4 is located approximately in the middle of the semicircle formed in the area 13, also indicated by a force F acting on this switching area 4. The effective switching area 4 is not only located exactly in the middle of the semicircle, but extends by a certain angular amount also to the left or right, in each case by about 30 °.

As can be seen in particular from FIG. 2, a series of stamps 5 extend from the inside of the semicircular region 13, starting from the center of the switching region 4, into the interior of the semicircular region 13. These stamps 5 are integral with the entire hose 1 formed, therefore also consist of elastic material. The punches 5 run through the entire semicircular area 13 and pass through the opening between the two strips 7. Then they essentially expand into one T-shaped cross-section, i.e. reach under these two strips 7.

The entire hose 1 described so far is thus made in one piece and consists of all elements, including the fastening elements 10, the side walls 14, the strips 7, the actuating area 4 and the stamp 5 made of elastomeric material. However, this material preferably does not have the same properties at all points in the cross section, for which purpose the different regions of the hose 1 must consist of different components of the elastomer. This is possible in terms of production technology and has the advantage that the fastening area 8 can be made of a relatively hard elastomeric material, while the actuation area 4, which must also have a spring action, can be made of softer material. In addition, the spring properties, which will be discussed later, can be adjusted by means of a suitable wall thickness and curvature.

The T-shaped stamps 5 have an electrically conductive coating on their ends 6, namely on their sides facing the switching region 4 and thus also the strips 7, thus forming a multiplicity 3 of movable contact elements. The strips 7 also carry contact elements on their sides facing away from the switching region 4, that is to say the sides facing the ends 6 of the punches 5. However, these are not arranged continuously on the two strips 7, but alternately and set to a gap with the contact elements 3 on the stamps 5, the contact elements 2 on the strips 7 overlapping the contact elements 3 on the stamps 5. The contact elements can be designed in any form, for example as a metallic coating, as glued foils, as metal plates or wires embedded in the elastomer or in another way, for example also using conductive plastic.

The closing edge safety works as follows:

In the idle state shown in FIGS. 1 and 2, the punches 5 are turned against the arrow F by elastic action of the semicircular wall 14 pulled up. Here, the T-shaped ends 6 of the contact stamp 5 are pressed against the strips 7 from below. In this way, a closed current path is created between the two varieties 2 and 3 of contact elements on the strips 7 on the one hand and the ends 6 of the punches 5 on the other hand. The current always flows alternately through a stationary contact element 2 and a movable contact element 3. This current flow is detected by evaluation electronics (not shown), which releases the motor of the roller shutter for as long as current flows.

When the switching area 4 of the hose 1 is actuated by an external force F, as shown in FIGS. 1 and 3, the plunger 5 is pressed downward, thus deforming the semicircular wall 14 in the switching area 4, in the direction of the fastening area 8. The end 6 of the stamp 5 is thus pressed into the square cavity 12, which is shown particularly well in FIG. 3. Here, the electrical connection between the contact element 3 of the actuated plunger 5 and the adjacent contact elements 2 on the strips 7 is interrupted. The interruption of the current flow is detected by the evaluation electronics, which then stops the motor of the roller shutter.

The device obviously works according to the opener principle and therefore only requires simpler system technology. In addition, the force at which the contact is to be broken can be set very precisely by a suitable choice of the elastomeric material and by a suitable combination of several components and by a suitable choice of the wall thicknesses and shapes. In addition, the construction with the large number of individual stamps ensures that the device functions practically along the entire length of the closing edge safety when actuated in only a small local area and when actuated.

Claims (5)

Closing edge safety device with an elastic hose (1), in which electrical contact elements (2, 3) are arranged, which are actuated in the event of lateral pressure (F) on a switching area (4) running along the hose (1), characterized in that the electrical Contact elements (2, 3) comprise a first plurality (2) of stationary and a second plurality (3) of movable contact elements, which are arranged alternately along the closing edge safety device, form a closed current path in the idle state and, in the actuated state, at least one movable contact element of the second plurality ( 3) from at least one stationary contact element of the first plurality (2) and thus the current path is interrupted. Closing edge safety device according to claim 1, characterized in that the convex switching area (4) of the elastic hose (1) has on its inside a multiplicity of stamps (5) of essentially T-shaped cross-section, the T-shaped ends (6) of which are at their ends the sides facing the switching area (4) have the second plurality (3) of movable contact elements and the first plurality (2) of stationary contact elements is arranged on at least one stationary cross bar (7) on a gap with the second plurality (3) and overlapping with them. Closing edge safety device according to claim 2, characterized in that the elastic hose (1) is made in one piece with the punches (5) and / or the or each strip (7). Closing edge safety device according to one of the preceding claims, characterized in that the elastic hose (1) consists of a multi-component rubber, the rear part (8) of the elastic hose (1) provided for fastening having a different Shore hardness than the switching area ( 4). Closing edge safety device according to claim 4, characterized in that the rear fastening area (8) is designed as a hinged jacket profile.

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